ng-flow issuing a GET, but not a POST

Question

I am trying to use ng-flow in angular for single image upload against an Express back end. When I select an image for upload, it appears that ng-flow is sending a GET request to my target (/admin/upload), then nothing else. I assume the GET is just part of the testChunks behavior, but i'm still unclear on why i'm not seeing a POST from the browser.

Here is the portion of my client dealing with ng-flow. It is based heavily on the code samples in ng-flow.

<div flow-init="{target: '/admin/upload'}" flow-prevent-drop
                     flow-drag-enter="style={border: '5px solid green'}"
                     flow-drag-leave="style={}"
                     test-chunks="false"
                     ng-style="style"
                     flow-files-submitted="$flow.upload()"
                     flow-file-success="$file.msg = $message">

                    <div class="container">
                        <h1>flow basic example</h1>
                        <hr class="soften"/>

                        <div class="row">

                            <div class="span6">
                                <h2>Buttons:</h2>

                                <span class="btn" flow-btn><i class="icon icon-file"></i>Upload File</span>

                            </div>
                        </div>
                        <hr class="soften">

                        <h2>Transfers:</h2>

                        <p>
                            <a class="btn btn-small btn-success" ng-click="$flow.resume()">Upload</a>
                            <a class="btn btn-small btn-danger" ng-click="$flow.pause()">Pause</a>
                            <a class="btn btn-small btn-info" ng-click="$flow.cancel()">Cancel</a>
                            <span class="label label-info">Size: {{$flow.getSize()}}</span>
                            <span class="label label-info">Is Uploading: {{$flow.isUploading()}}</span>
                        </p>
                        <table class="table table-hover table-bordered table-striped" flow-transfers>
                            <thead>
                            <tr>
                                <th>#</th>
                                <th>Name</th>
                                <th>Size</th>
                                <th>Relative Path</th>
                                <th>Unique Identifier</th>
                                <th>#Chunks</th>
                                <th>Progress</th>
                                <th>Paused</th>
                                <th>Uploading</th>
                                <th>Completed</th>
                                <th>Settings</th>
                            </tr>
                            </thead>
                            <tbody>
                            <tr ng-repeat="file in transfers">
                                <td>{{$index+1}}</td>
                                <td>{{file.name}}</td>
                                <td>{{file.size}}</td>
                                <td>{{file.relativePath}}</td>
                                <td>{{file.uniqueIdentifier}}</td>
                                <td>{{file.chunks.length}}</td>
                                <td>{{file.progress()}}</td>
                                <td>{{file.paused}}</td>
                                <td>{{file.isUploading()}}</td>
                                <td>{{file.isComplete()}}</td>
                                <td>
                                    <div class="btn-group">
                                        <a class="btn btn-mini btn-warning" ng-click="file.pause()" ng-hide="file.paused">
                                            Pause
                                        </a>
                                        <a class="btn btn-mini btn-warning" ng-click="file.resume()" ng-show="file.paused">
                                            Resume
                                        </a>
                                        <a class="btn btn-mini btn-danger" ng-click="file.cancel()">
                                            Cancel
                                        </a>
                                        <a class="btn btn-mini btn-info" ng-click="file.retry()" ng-show="file.error">
                                            Retry
                                        </a>
                                    </div>
                                </td>
                            </tr>
                            </tbody>
                        </table>

                        <hr class="soften"/>

                        <div class="alert" flow-drop flow-drag-enter="class='alert-success'" flow-drag-leave="class=''"
                             ng-class="class">
                            Drag And Drop your file here
                        </div>
                    </div>
                    </div>
            </div>


        </div>

Here is an extract from my express.js file. You will notice I have defined an app.post and an app.get method for the upload URL.

var express = require('express'),
favicon = require('static-favicon'),
morgan = require('morgan'),
compression = require('compression'),
bodyParser = require('body-parser'),
methodOverride = require('method-override'),
cookieParser = require('cookie-parser'),
session = require('express-session'),
errorHandler = require('errorhandler'),
path = require('path'),
config = require('./config'),
passport = require('passport'),
mongoStore = require('connect-mongo')(session);

var multipart = require('connect-multiparty');
var multipartMiddleware = multipart();

process.env.TMPDIR = 'tmp';
var flow = require('../../flow-node.js')('tmp');

/**
* Express configuration
*/
module.exports = function(app) {
var env = app.get('env');

if ('development' === env) {
app.use(require('connect-livereload')());

// Disable caching of scripts for easier testing
app.use(function noCache(req, res, next) {
  if (req.url.indexOf('/scripts/') === 0) {
    res.header('Cache-Control', 'no-cache, no-store, must-revalidate');
    res.header('Pragma', 'no-cache');
    res.header('Expires', 0);
  }
    if(path.extname(req.url) == '.js'){
        res.set('Content-Type','text/javascript');

    }
 }
  next();
});

app.use(express.static(path.join(config.root, '.tmp')));
app.use(express.static(path.join(config.root, 'app')));
app.set('views', config.root + '/app/views');
  app.set('scripts', config.root + '/app/scripts');
  app.set('bower_components', config.root + '/app/bower_components');

  app.post('/admin/upload', multipartMiddleware, function(req, res) {
      console.log('in POST...');

      flow.post(req, function(status, filename, original_filename, identifier) {
          console.log('POST', status, original_filename, identifier);
          res.send(200, {
              // NOTE: Uncomment this funciton to enable cross-domain request.
              'Access-Control-Allow-Origin': '*'
          });
      });
  });

  app.get('/admin/upload', function(req, res) {
      flow.get(req, function(status, filename, original_filename, identifier) {
          console.log('GET', status);
          res.send(200, (status == 'found' ? 200 : 404));
      });
  });

  app.get('/admin/download/:identifier', function(req, res) {
      flow.write(req.params.identifier, res);
  });
  }

Have I missed something fundamental in the markup for ng-flow? or something in Express? Or? Thank you in advance.

Answer 1

I had the same issue and the solution i found was to set testChunks:false

flow-init="{target: url, testChunks:false}"

Answer 2

I experienced the same issue after having used ng-flow without issue for quite some time.

Setting testChunks to false does work however I wanted to keep the testChunks functionality to speed up file resumes.

After some digging I found that for some reason the 404 error code was in the list of permanent errors in the flowjs distribution files (dont recall it being in there previously). I just amended my flow-init to exclude 404 and everything went back to normal.

              flow-init="
                {
                  target: '/services/upload', 
                  query: injectUploadID,
                  permanentErrors: [415, 500, 501]
                }"